Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 14, Problem 14.16QAP
Interpretation Introduction
(a)
Interpretation:
The formula of the complex should be determined.
Concept introduction:
In photometric titration, absorbance of the solution is measured to determine the endpoint of the titration. This is based on the theory that the absorbance of a solution is directly proportional to the concentration of analyte. A graph is plotted between absorbance versus volume of titrant added.
Interpretation Introduction
(b)
Interpretation:
The molar absorptivity of the complex should be determined.
Concept introduction:
The Beer-Lambert Law is:
where,
A − absorbance
l − length of the solution light passes through (cm)
c − concentration of solution (mol/L)
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
The absorbance of a 1.05x10-5 M Fe+3 determined at 580 nm using a 2.50-cm cell was said to be 0.200. What is the molar absorptivity of this solution in liters/mole cm?
Mercury(II) forms a 1:1 complex with triphenyltetrazolium chloride that exhibits an absorption maximum at 255 nm. The mercury(II) in a soil sample was extracted into an organic solvent containing an excess of TTC , and the resulting solution was diluted to 100.0 mL in a volumetric flask. Five-milliliter aliquots of the analyte solution were then transferred to six 25-mL volumetric flasks. A standard solution was then prepared that was 5*10^-6 M in . Volumes of the standard solution shown in the table were then pipetted into the volumetric flasks, and each solution was then diluted to 25.00 mL. The absorbance of each solution was measured at 255 nm in 1.00-cm quartz cells. Please solve and explain these questions: A.) Enter the given data pictured above into a spreadsheet and show the correct standard additions plot B.) Determine the slope and the intercept of the line C.)Determine the standard deviation of the slope and the intercept. D.) Calculate the concentration of Hg(II) in the…
The molar absorptivity (ε) of the FeSCN2+ complex ion is 4700 M-1 · cm-1 at a wavelength of 450 nm. Using a 1-cm sample tube, you measure the absorbance as (2.0x10-1). What is the concentration of FeSCN2+?
Chapter 14 Solutions
Principles of Instrumental Analysis
Ch. 14 - Prob. 14.1QAPCh. 14 - A 0.4740-g pesticide sample was decomposed by wet...Ch. 14 - Sketch a photometric titration curve for the...Ch. 14 - Prob. 14.4QAPCh. 14 - Prob. 14.5QAPCh. 14 - The accompanying data (1.00-cm cells) were...Ch. 14 - A 3.03-g petroleum specimen was decomposed by wet...Ch. 14 - Prob. 14.8QAPCh. 14 - Prob. 14.9QAPCh. 14 - The acid-base indicator HIn undergoes the...
Ch. 14 - Prob. 14.11QAPCh. 14 - Prob. 14.12QAPCh. 14 - Copper(II) forms a 1:1 complex with the organic...Ch. 14 - Aluminum forms a 1:1 complex with...Ch. 14 - Prob. 14.15QAPCh. 14 - Prob. 14.16QAPCh. 14 - Prob. 14.17QAPCh. 14 - Prob. 14.18QAPCh. 14 - Prob. 14.19QAPCh. 14 - Given the Information that...Ch. 14 - Prob. 14.21QAPCh. 14 - Mixing the chelating reagent B with Ni(II) forms...Ch. 14 - Prob. 14.23QAP
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.Similar questions
- The absorbance of a 0.00105% m/v solution of tolbutamide in methanol when measured in a 1 cm path length cell was found to be 0.796 at 228 nm. Calculate the specific absorbance.arrow_forwardPd(II) and Au(II) can be determined simultaneously by the reaction with methiomeprazine (C 19 H 24 N 2 S 2 ). The maximum absorption for Pd occurs at 480 nm, while for the Au complex it is at 635 nm. A sample of 25 mL was treated with excess of the complexant and then diluted to 50.0 mL. Calculate the molar concentrations of Pd(II) and Au(II) in the sample. The data are found in the table below and the bucket used was 1.0 cm.arrow_forwardThe accuracy of a spectrophotometer can be evaluated by preparing a solution of 60.06-ppm K2Cr2O7 in 0.0050 M H2SO4 and measuring its absorbance at a wavelength of 350 nm using a cell with a pathlength of 1.00 cm. The absorbance should be 0.640. What is the molar absorptivity of K2Cr2O7 at this wavelength?arrow_forward
- If you are measuring manganese (Mn) absorption using AAS, which hollow cathode lamp would you select as your source and why?arrow_forwardThe molar absorptivity (ε) of the FeSCN2+ complex ion is 4700 M-1 · cm-1 at a wavelength of 450 nm. Using a 1-cm sample tube, you measure the absorbance as (2.0x10-1). What is the concentration of FeSCN2+? What is your answer? _____________x10^_____arrow_forwardRadiation of wavelength 300 nm was passed through a chemical actinometer containing 10 ml of a 0.05M oxalic acid solution and 0.01M uranyl sulphate. The concentration of oxalic acid solution became 0.03M after absorption of 80J radiation energy. Calculate the quantum yield of the photodecomposition of the oxalic acid?arrow_forward
- Topic: Transmittance and absorbance, lambert-beer law A 0.01 M solution in KCr (C2O4) 2 (H2O) 2 in a 1 cm cell absorbs half the radiation that a 0.001 M solution of Br2 in a 5 cm thick cell. At 250 nm the molar absorptivity coefficient for Bromine is 150. Calculate the coefficient of molar absorptivity of the oxalate complex.arrow_forwardThe absorbances of solutions containing K2CrO4 in 0.05 M KOH were measured in a 1.0-cm cell of 375 nm. The following results were obtained: Calculate the concentration of K2CrO4 (g/L) if the A is 0.550.arrow_forwardA standard solution was put through appropriate dilutions to give the concentrations of iron shown in the table that follows. The iron(II)-1,10-phenanthroline complex was then formed in 25.0-mL aliquots of these solutions, following which each was diluted to 50.0 mL. The following absorbances (1.00-cm cells) were recorded at 510 nm: Calculate the concentration, in ppm, of a sample with an abosrbance of 0.829. Fe(II) concentration (ppm) A510 4.00 0.160 10.0 0.390 16.0 0.630 24.0 0.950 32.0 1.260 40.0 1.580arrow_forward
- The absorbance values observed during the determination of the complex stoichiometry with the Job method using the spectroscopic method were plotted and the following correct equations were obtained. According to this, what is the n value of the compound formed by Fe + 3 and SCN- ions?1. Line equation: y = 2.6188x + 0.1608 2. Line equation: y = -2.5963x + 2.7203arrow_forwardCalculate the molar absorptivity and absorbance of a 1.00 x 104 M solution, which has atransmittance of 32.1% , when the path length is 2.5 cm at 650 nm. (arrow_forwardA dual beam UV-visible spectroscopy was used to determine the levels of Fe(II) in the run-off water of a local mine using the ferrozine assay (i) During a check of the instrument a step-like feature at 360 nm was observed in spectrum of the standard. Suggest what may give rise to this with reference to the instrument configuration and comment on how it may be remedied. (ii) The molar absorptivity of the [Fe(Ferrozine)3]2+ complex is 27900 cm−1 M−1 at 562 nm in aqueous solution (pH 5.5). If the EU maximum contaminant level for Fe is 200 ug /L and the contract required detection limit is 100 ug/L, comment on the suitability of the assay for the detection of iron. (iii) Determine the sample range, in terms of concentration and ppm, of Fe(II) that can be confidently analysed by UV-visible spectroscopy using a 1 cm cuvette. Explain with reference to an appropriate equation and solution phenomena, the origin of the limitations that define this rangearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning